A car navigation system is a high-technology system for receiving position information by identifying a current position of a vehicle and providing various services for providing a route guide, traffic guide, peripheral information, and additional information by combining the position information with geographic information. Furthermore, there has already been commercialized a car navigation system combined with global positioning system (GPS) technologies for vehicles capable of relaying driving directions to a driver through a display screen or voice signal and a geographic information system (GIS). This car navigation system is being employed for smooth land and water transport operations as in public transportation systems including delivery trucks, and quick delivery services.
A GPS receiver is mounted in a mobile device such as a personal digital assistant (PDA) so that a map and current position information of the mobile device are displayed on a screen of the mobile device. The GPS technology for a mobile terminal is applied to provide various information units such as traffic, shopping and caf? information, etc. associated with the current position.
A device for telematics, the combination of telecommunication and information, is mounted in vehicles, and couples wireless communication technology, GPS technology, GIS technology and call center technology to the vehicles. Moreover, the telematics device provides real-time traffic and living information for drivers, a method for taking action against an emergency situation, remote vehicle diagnosis, car accident prevention, theft prevention, driving route glide, and is coupled to a vehicle on-board controller, an audio system, a display, etc., such that the telematics device is developing into a mobile office concept.
There is a problem in that the vehicles must install the high priced telematics device for supporting the wireless mobile communication, GPS and GIS, so that the above-described services can be provided.
Thus, when the real-time traffic and living information and driving route information are desired using mobile phones carried by most of the drivers, the GPS receiver must be mounted on a hands-free set, and hence the drivers can receive various information units by accessing the Internet through the mobile phones after the GPS receiver identifies the positions of their vehicles.
FIG. 1 is a block diagram illustrating the configuration of a navigation system using a conventional mobile phone.
As shown in FIG. 1, the navigation system includes a mobile phone 40 for performing wireless communication through a wireless communication network 50; a service center 60 coupled to the wireless communication network 50 for analyzing real-time traffic information and calculating an optimum route; a GPS receiver 10 for identifying current position information from a satellite; a direction sensor 22; and an acceleration sensor 24. Moreover, the navigation system includes a navigator 20 for storing the position information received from the GPS receiver 10, accessing the service center 60 through the mobile phone 40, controlling a transmission operation for position information and a reception operation for various information units, and outputting the result through the mobile phone 40, and a mobile phone mount 30 on which the mobile phone 40 is mounted. The mobile phone mount 30 supplies power to the mobile phone 40.
In this case, the GPS receiver 10, the navigator 20 and the mobile phone mount 30 are mounted in a vehicle in a hands-free form and are formed so that they can be separated from the mobile phone 40.
The operation of the navigation system using the conventional mobile phone will be described with reference to a flowchart illustrating a method for operating the navigation system using the conventional mobile phone shown in FIG. 2.
First, the navigation system downloads an operating program from the service center 60 through the wireless communication network 50 using the mobile phone 40, identifies current position information through the GPS receiver 10, and registers the identified position information in the service center 60 (S10).
Then, the navigation system enables a driver to input information on a destination (S12). If so, the service center 60 produces traffic information analyzed in real time and an optimum route according to the current vehicle position and the destination (S14).
Then, the service center 60 transmits analyzed data to the mobile phone 40 (S16).
Then, the navigator 20 performs a road guide operation through the mobile phone 40 according to data transmitted through the mobile phone 40 and a vehicle traveling state based on the direction sensor 22 and the acceleration sensor 24 (S18).
In order that the traffic information and road guide service can be provided, the road traffic state must be identified and information of the identified road traffic state must be organized in a database of the service center 60. Traffic information services are being provided using information units acquired by a method for collecting traffic information through closed circuit televisions (CCTVs) installed on map roads by the Road & Transportation Builders Association and information providers, a method for collecting traffic information through traffic correspondents, a method for collecting traffic information through loop sensors installed on roads, a method for collecting traffic information using beacons, etc.
There is a problem in that high cost is required to operate vehicles for acquiring or collecting the traffic information or to purchase the traffic information from the information providers. Furthermore, there are another problems in that traffic information is not reflected in real time because it is difficult for the traffic information to be continuously measured and hence customer demand cannot be satisfied.
To address the above-described problems, the applicant filed applications entitled ‘METHOD FOR OBTAINING TRAFFIC INFORMATION USING BILLING INFORMATION OF MOBILE TERMINAL’ having Ser. Nos. 10-2003-0019644 (Mar. 28, 2003) and 10-2003-0037190 (Jun. 10, 2003) with the Korean Intellectual Property Office.
When a mobile terminal attempts a telephone call on a highway (S31) as shown in FIG. 3, a system receives billing information necessary for performing a billing operation (S32), obtains an identification number of a mobile terminal from the received billing information (S33), receives a position registration request from a corresponding mobile terminal (S34), tracks a moving time between base stations according to registered position information (S35), and obtains information of a highway traffic state in real time by producing an average speed on a section-by-section basis (S36 and S37).
However, because at least one base station is shared between a local road and a highway in a section containing the local road and the highway parallel to the local road, the system cannot determine that a vehicle is driven on the local road where the vehicle is driven on the local road parallel to the highway after coming out of a highway tollgate. In this case, the system determines that the vehicle is still being driven on the highway. Thus, because the system produces information on a moving speed of the vehicle on the highway through a moving speed of the vehicle driven on the local road, it is difficult for the system to obtain information of a traffic state of the highway due to crosstalk between the highway and the local road.